Bone marrow has been used as an easily-accessed source of hematopoietic stem cells (HSCs) and other regenerative cell types such as mesenchymal stromal/stem cells (MSCs). Since the bone marrow is a renewing tissue, it can provide a useful source of renewable cells for regenerative medicine applications, particularly those where autologous cells are preferred.
Conventionally, bone marrow aspirates have been processed by separating cellular components. These methods can de-bulk the marrow by separating out erythrocytes (RBCs), which are conventionally regarded as having no value, and potentially even detrimental in regenerative medicine applications. In general, these methods of separation have exploited different physical characteristics of RBCs to enrich in the mononuclear cell fraction which contains the HSCs and MSCs.